source

type ChangeSet struct {
	Data      []byte    // binary data
	Checksum  string    // md5 sum
	Format    string    // type of the data
	Source    string    // name of the data source
	Timestamp time.Time // time stamp
}

type Option func(o *Options)

type Options struct {
	// Encoder
	Encoder encoder.Encoder
	// for alternative data
	Context context.Context
}

type Source interface {
	Read() (*ChangeSet, error) // read from source, to change set
	Watch() (Watcher, error)   // watch the source change
	String() string            // return the name of the data source
}

type Watcher interface {
	Next() (*ChangeSet, error) // Method returns the changed data set when the data source changes
	Stop() error               // Method stops the data source change monitor
}